Coupling device of vacuum cleaners



April 30, 1940. K. CONTENT COUPLING DEVICE 0F VACUUM CLEANERS Filed June 22, 1939 a j. yk

- lNvENT-o MKM-cm Magma/Xg Patented Aprff), 1940v s COUPLING DEviCEfoF VACUUM CLEANERS l t Klara Content, Voorburg,` Netherlands;yassignery to Thahur, Industrieele enr Technische Handel-- maatschappij N.,V., The Hague, Netherlands Application June. 22, 1939, serial ,Nogzsoaev In the Netherlands June 17,

This invention relates to coupling devices for connecting a vacuum cleaner tube or another detachable part -tov a vacuum cleaner casing. Morel particularlythe invention is concerned with 5 a bayonet lcoupling of the kind in'lwhich the coupling parts xedi to the vacuum cleaner icas ing is provided with one lor more inwardly projecting guide members, whilst the other part of the coupling is connected to the vacuum cleaner tube and consists of a revolvable `cylindrical ring lwhich is provided with tangential helicoidal surfaces at the outside, which surfaces are radapted to cooperate withthe guide members of the fixed coupling parts. y i

f5 One of the'objects of my invention is tofdevise a new and improved coupling device of this kind, which is efficient in construction, simple in manufacture andveasy in handling.y Another object'of my invention is to provide a coupling device which is particularly' suitable for use in vacuum K cleaners, v

Another object of my invention is to devise a coupling device in which .the detachable coupling part has no projecting parts, .which on a vacuum '25 cleaner tube can catch in carpets and furniture and can cause other damages. i -v Another object of my invention is to provide a coupling( device which cannot be turned ,30 through so that the coupling does not bite..

A still further object of. my invention is to *provide a coupling device in which the locking cams'are well protected and enable at the same time a good guiding and rigid fixation of the de- 35 tachable coupling part in such a manner that the coupling cannot get looseprematurely.

AnotherV objectof my invention is to provide a coupling device which vcan be made very durable and enables at the same time a very efficient tightening. y

Another object ofy my invention is to provide a coupling device, having no'floose or detachable parts at the detachable coupling part.

In contrast'to the known constructions of the kind referred to according to the invention the bayonet coupling comprises a coupling part fixed to the vacuum cleaner casing rand consisting of a stepwise widening annular member of which the widened partv of the opening of the member is adapted to receivev the revolvable part ofthe detachable couplingy part and is provided between the bottom and thefree edge with a number of inwardly projecting cams or other guidingmembers, whilst the other coupling part consists of a 55 mainly cylindrical ring which is revolvably con- Anected to the end of the vacuum cleaner tubeand provided with tangential helicoidal surfaces at 'dinal grooves opening to the free end edge of e. g. during putting away of the vacuum cleaner l f cleaner tube and the part of the detachable couthe Aoutside rbeing adapted to cooperate with the said ixedcams or guide members of thef'Xed l couplingpart., thehelicoidal surfaces vof there'- 5 .volvable ringbeing carried out as groovesfhollowed out in the materialof the ringI running substantially` in the circumferential direction thereof, and ,each corresponding with rlongitu the revolvable ring. e, I N n v In this connection itis observedthat theprof vision of a .single groove in the detachable coup'- ling part, in such a manner 'thatthi's groove'is adapted to cooperate with'a projection 'at the inside of the fixed coupling'part is known in itself. v In the known construction referred toth'e coli-k piling, however, is not bayonet couplingbut a friction 'coupling in which the'couplingparts are i clamped togetherV in the coupling position -by means ofrconical friction-surfaces. FurthermoreLthegroovedcoupling partis rigid-ly connected to--the vacuuml cleaner tubeiso that-the couplingcan easily get loose in` spite of-the bayonet safetylocking. 25

The recesses of the detachable coupling `part forming the helicoidal surfaces according to the invention have preferably a depth which is about equal orsmaller than the half thickness on that place of the vmaterial lof the u ring forming thisv coupling part. In thisfmanner the coupling part `connected tothe vacuum cleaner tube becomes considerably stronger, whilst 'on the other hand this construction venables a very efficient tightening between the two cooperating coupling parts. This tightening-occurs preferably by providing the iixed coupling` part in the bottom wall with a tighteningy ring which, in the coupling position of the `two `coupling parts, covers the joint betweeny the bent out revolvable edge of the vacuum pling part surrounding this edge of the tube. In this manner dust is prevented from getting between the two coupling parts. o

The invention will now be described with reference to the accompanying drawing, in which a preferred embodiment of the invention is shown. In the drawing:

Fig. l shows a longitudinal section of a coupling device according to `the invention,

Fig. 2 a front viewvon a somewhat reduced scale of the coupling part connected to the vacuum cleaner tube,

Fig. 3 shows a side view of this coupling parton a reducedscale and n 55 i connection is obtained in this case in that the sleeve 2 runs through the coupling part 3 and this latter is provided internally with an annular narrowing 4 on both sides of which the sleeve is somewhat widened. Thus the sleeve can rotate freely with respect to the coupling part 3, but

lies absolutely fixed in axial direction.

The coupling part xed to the vacuumcleaner tube consists in the shown embodiment of a mainly cylindrical front part 5 with grooves 6, hollowed out in the material thereof, and having. a tangential helicoidal surface 1. The grooves 6 are closed at one end and have at theend, nearest to the free edge of the front part 5, a connection vwith an axial or approximately axial groove 8,

opening to the free end of the revolvable ring 5 (Fig.'?,). The rear part 9 in provided with a milled edge I in order,` to facilitate turning the ring for coupling and decoupling purposes.

The coupling part xed to the vacuum cleaner casing consists mainly of an annular member II` which is provided with internally projecting cams or guide members I2. In the shown embodimentl .three cams I2 are provided, but if desired alsoone or another number of cams can be used.

The cams I2 have such dimensions that they vcan easily be brought into the grooves 6 through thepassages 8.

The tightening is obtained by means of a tightening ring I3, which is connected to an internal angeor wall I4 of this coupling part. This can e. g. take place by inserting the ring in an annular dovetailed groove of the flange. The dimensions of the cooperating coupling parts are 'in this connection to be chosen in such a manner that the front edge of the coupling part fixed to the vacuum cleaner tube lies in the coupling position near to the flange I4. In order to prevent eventual leakages along the sleeve 2 and the coupling part fixed to the vacuum cleaner tube, the sleeve can be bent out against the front edge of this coupling part. In this manner it can be obtained that .the end edge I5 of the sleeve abuts also against the tightening ring I3.

tending into said recess.

The coupling part II can e. g. be connected to the vacuum cleaner casing I8 with screws I6, but also with a threaded end part I'I as shown in dotted lines in Fig. 1 or in'another manner.

The invention is above described With reference to a preferred embodiment, but it Will be clear that the invention is not restricted .to Lthis embodiment and that numerous changers-fand omissions could be made without departing from its spirit. Thus e. g. the helicoidal surfaces l, instead of being formed by recesses in the material, can also be formed as projecting cam-surfaces, which together form a ring with recesses.

- What is claimed, is:

1. `A coupling device for detachably connecting a vacuum cleaner tube to a vacuum cleaner casin'grcomprising an annular member rigidly se cured to the casing and an annular member rotatably connected with the tube, the iirst annular member presenting an internal annular recess defined by atubular portion coaxial with the annular members and a vertical annular flange ad- Cil jacent the casing, the second annular member embodying a portionadjacent the free end of said tubular portion for eiecting rotation of the member and a tubular portion. extending into the recess inthe rst member, cam lugs projecting inwardly from said first tubular portion and angular grooves extending partially through said second tubular member from the outer wall thereof, the grooves embodying portions parallel with the axes of said members for initially receiving said lugs and circumferential portions having cam walls for receiving said lugs and effecting movement of said members towardfeach other upon rotation of the second member.

2. A coupling according to vclaim 1` together with a seal ring seated in an: annular groove in said vertical ange and projecting into said recess for Vengagement `of the free end of said a sleeve having a portion thereof surrounding an 45 end of the tube and connected thereto and a portion projecting beyond theend of the tube, a lcircumferential recess in the projecting portion of the sleeve, and al circumferential rib on the inner wall of said second tubularvporton exf KLARA CONTENT. 

